A Springfield police cruiser at night.(Republican file photo by Robert Rizzuto)

SPRINGFIELD -- Four men were arrested on firearms and drug charges shortly before 2 a.m. Thursday after police were directed to a ShotSpotter activation and found the men hiding in a vehicle along with a stash of weapons and drugs.

Captain Larry Brown said the 1:46 a.m. activation by the city's gunfire plotting system indicated a shot was fired on Northampton Avenue and police cruisers were vectored to the spot.

Upon arrived, officers noticed a vehicle which appeared empty, until the driver put his head up. Officers ordered everyone out of the car, and four men stepped out. An examination of the vehicle showed the men were carrying a sawed off shotgun and two revolvers, as well as a quantity of marijuana.

The names of those arrested and the amount of the marijuana recovered is incomplete at this time. Masslive.com will update this story as information becomes available.